Seat Design of Drivers Cabin for New EMU Rakes of Mumbai

Abstract

The Mumbai Suburban Railway is the first rail system in India which began services in Mumbai in 1867 transports today about 6.3 million passengers daily and has the highest passenger density in the world. The drivers (Motormen) are driving more than 8 hours in a day. They are suffering from musculoskeletal and psychophysical stresses due to their unsuitable workstation. Considering the age old existing workstation design a new ergonomics based design approach is undertaken to redesign the workstation with advanced instrumentation. At present the operation is mostly in standing posture and drivers have difficulty in external visibility along with associated musculo-skeletal and psychophysical stresses with special reference to shorter drivers as per the UIC code while they are driving in sitting posture. The lack of ergonomics considerations in workstation design, layout, chair design, leg room while sitting, visual cone in horizontal and vertical plane, communication, personal space and so on as against operating the train, passenger behavior, trespassing etc. depicts a list of risk factors in driving train. This paper highlights on the modification made in the chair design for the motormen based on the new concept workstation provided to us. A user centered approach based on drivers’ behavior and understanding the issues were made on board by personal interview method and observation method. 62 different anthropometric measurements of 50 motormen age range 30 to 60 years were collected by using 3D whole body scanner. Based on 3D anthropometric data a 3D model of the chair and the workstation were made by using Solidworks CAD software. The CAD drawing was then converted to a full scale prototype for simulation study. A new concept horizontal and vertically adjustable chair with adjustable footrest was designed and fabricated o fit in to the given workstation to accommodate 5th to 95th percentile motorman. Visual limits in horizontal and vertical planes were also taken into account while optimizing the static and dynamic dimensions of chair. Care was taken to provide proper backrest, hand rest and footrest. Driver comfort was also taken into consideration while designing the chair.